The present invention relates in general to an improved facia border for use around the periphery of a building roof, and in particular to a facia border for use on flat-roofed structures.
A special need arises in flat-roofed structures for facia borders which are adapted for anchoring roofing sheet material without puncturing the material, and for providing a gravel stop to contain the rock composition overlying the sheet material, when used. The roofing industry has experienced a great deal of advancement in the development of roofing materials which have an extended life and which are resistant to extreme environmental conditions. According to current construction techniques, metallic facia borders are utilized to anchor the roofing sheet material around the peripheral edge of the roof, as well as in many cases provide a boundary for containing the gravel overlay. Because a primary aim of a high quality roofing sheet material is to prevent the leakage of water, it is counterproductive to utilize facia border elements which have a tendency to puncture the material during installation or expose of the sheet material to sharp edges of the facia border.
One type of facia border which has enjoyed moderate success is described in U.S. Pat. No. 4,071,987 by Hickman. With this construction, however, the top metallic edge of the facia anchor can easily pierce the roofing sheet material. Moreover, the Hickman facia border is not a rigid unit when installed and thus any horizontal pressure on the unit by ladders or by workmen stepping on the it will either stretch or wrinkle the sheet material, or weaken it to the extent that leakage becomes a possibility.
Another attempt to provide an answer to facia problems on flat-roofed buildings is described in U.S. Pat. No. 3,405,485 by Edwards. While this type of facia border may be effective, it suffers the disadvantage that the completed structure is comprised of many complex-shaped pieces. As a result, installation becomes complex and time consuming, thereby increasing material and labor costs. With this arrangement, the elongate edge of the complex-shaped counterflashing element engages the roofing sheet material and increases the chance of puncturing or piercing the material.
Other varieties of facia borders include U.S. Pat. No. 4,155,203 by Wolma which discloses a rigid structure, but which anchors the roofing sheet material by pinching, and thus partially puncturing the sheet material. U.S. Pat. No. 3,012,376 by Reddy et al. shows a facia border with a coping member which is easily snap-lock installed, but which lacks the ruggedness and rigidity necessary for commercial use.
With the foregoing in mind, it is seen that there is a need for a facia border which can be easily constructed, easily installed and is rugged and rigid. Of paramount importance, there is a need for a facia border which anchors the roofing material in such a way as to eliminate any possibility of rupturing, puncturing, or stretching the sheet material.